{"product_id":"yokogawa-acm12-serial-communication-module","title":"YOKOGAWA ACM12 Serial Communication Module","description":"\u003ch2\u003eYOKOGAWA ACM12 Communication Module\u003c\/h2\u003e\n\u003cp\u003eThe \u003cstrong\u003eYOKOGAWA ACM12\u003c\/strong\u003e, also cataloged as the \u003cstrong\u003eACM12\u003c\/strong\u003e Communication Module, operates as a dedicated hardware component for serial data exchange within industrial control networks. This module provides an RS-422\/RS-485 physical interface, facilitating point-to-point or multipoint connectivity for external devices requiring half-duplex communication protocols.\u003c\/p\u003e\n\u003cp\u003e\u003ci\u003eNote: The provided documentation contains conflicting data regarding the ACM12 functionality (referencing both serial communication and 16-channel analog input). This datasheet adheres to the primary serial interface specifications.\u003c\/i\u003e\u003c\/p\u003e\n\u003ch3\u003eHardware Specifications\u003c\/h3\u003e\n\u003cfigure class=\"table\"\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003e\u003cstrong\u003eParameter\u003c\/strong\u003e\u003c\/th\u003e\n\u003cth\u003e\u003cstrong\u003eSpecification\u003c\/strong\u003e\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel\u003c\/td\u003e\n\u003ctd\u003eACM12\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eYOKOGAWA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOrigin\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.3 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDimensions\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOperating Temp\u003c\/td\u003e\n\u003ctd\u003e-20 deg C to 70 deg C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower Consumption\u003c\/td\u003e\n\u003ctd\u003e310 mA (5 V DC), 500 mA (24 V DC)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInterface\u003c\/td\u003e\n\u003ctd\u003eRS-422\/RS-485 (1 port)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSpeed\u003c\/td\u003e\n\u003ctd\u003e1200 to 19200 bps\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTransmission Distance\u003c\/td\u003e\n\u003ctd\u003eMax 1200 m\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/figure\u003e\n\u003ch3\u003eIndustrial Serial Communication Characteristics\u003c\/h3\u003e\n\u003cp\u003eThe \u003cstrong\u003eACM12\u003c\/strong\u003e utilizes start-stop synchronization for serial data transmission, supporting both ASCII and binary coding formats. To maintain data integrity over the maximum 1200 m transmission distance, the module implements parity checking (Odd\/Even\/None) and configurable character\/stop bit lengths. When configured for multipoint connectivity, the module functions as a deterministic node in the communication chain, requiring precise termination at both ends of the RS-485 bus to prevent signal reflections.\u003c\/p\u003e\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cp\u003eQ: Why is \"No parity\" unavailable at a communication speed of 19200 bps?\u003c\/p\u003e\n\u003cp\u003eA: The restriction is due to timing constraints within the module's UART processing logic at higher baud rates. When operating at 19200 bps, the system requires the parity bit to ensure sufficient frame synchronization and error detection.\u003c\/p\u003e\n\u003cp\u003eQ: How can signal reflections be mitigated in a 1200 m multipoint network?\u003c\/p\u003e\n\u003cp\u003eA: Reflections are typically caused by impedance mismatch. Ensure that the bus is terminated at both ends using 120 Ohm resistors and that the cable characteristic impedance is matched to the transceiver requirements.\u003c\/p\u003e\n\u003ch3\u003eField Installation Guidelines\u003c\/h3\u003e\n\u003col\u003e\n\u003cli\u003eEnsure the RS-422\/RS-485 wiring utilizes shielded twisted-pair cabling to minimize electromagnetic interference over long distances.\u003c\/li\u003e\n\u003cli\u003eVerify that the shield is grounded at a single point (typically the master node) to prevent ground loops between distributed devices.\u003c\/li\u003e\n\u003cli\u003eCheck all baud rate, parity, and character length DIP switch or software settings against the requirements of the connected field devices before energizing the module.\u003c\/li\u003e\n\u003cli\u003eConfirm that the total bus length does not exceed 1200 m; verify that the cumulative node count does not exceed the transceiver's electrical loading limits.\u003c\/li\u003e\n\u003cli\u003eSecure all connections using the pressure clamp terminals, ensuring no exposed wiring beyond the cable entry point to prevent short circuits.\u003c\/li\u003e\n\u003c\/ol\u003e","brand":"Yokogawa","offers":[{"title":"Default Title","offer_id":43624297136218,"sku":"ACM12","price":99.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0710\/5957\/0778\/files\/485_7fda4336-1d82-4ae7-bf07-f8888d0a5b65.jpg?v=1783583173","url":"https:\/\/www.spareoil.com\/es\/products\/yokogawa-acm12-serial-communication-module","provider":"SpareOil Automation","version":"1.0","type":"link"}